PURPOSE: To provide a pigment-containing polymer for use in forming a melt spun fiber which is resistant to an acid-dye and stains, by a process comprising the step of polymerizing a mixture containing a polyamide-forming monomer and a sulfonate, the step of pigmenting the resulting polymer and the step of subjecting the resulting mixture to a specific treatment.
CONSTITUTION: This preparation process comprises the step of polymerizing a mixture containing a polyamide-forming monomer (for example, caprolactam) and a sulfonate (for example, sodium sulfoisophthalate), the step of incorporating a pigment or a pigment composite consisting essentially of one or more pigments and a polymer matrix into the resulting sulfonated polyamide copolymer and the step of chemically blocking at least a portion of amino end groups present in the resulting pigment-incorporated sulfonated polyamide copolymer with a chemical blocking agent (for example, butyrolactone).
ANDORIYUU EMU KUUNSU ZA SAADO
DEIBITSUDO ENU DEIKUSON
